Home › Forum › Ask A Member › ’60s lark / seahorse swap › Re: ’60s lark / seahorse swap
Yes, they are interchangeable. I have done it. Yours is even closer in design, between the two than mine were. But like Chris says. Just run the Lark until it dies, then use the Super Sea Horse powerhead.
I once put a 1968 Lark X powerhead on a 1959 Johnson RDS -21B and it worked awesome!! Five more horse, without any mods, plus I had a 50:1 motor.
I also had a ’61 Lark III and it was a nice unrestored copy. Very reliable motors, in my opinion and will last for years if treated right. One good preventative for keeping the crankshaft from breaking, is make sure that your prop and drive pin are in top knotch condition, because it’s when these motors over rev without a load, is what does most of the breaking. Never over rev these, while in neutral, either, because you could possibly see some metal come unglued right before your eyes.